Improvement in sewing-machines



1 'w. A. MAcK.

- Sewing Machine.

No. 111,359. Patented Jan'y 31, 1871 y UNITED STATES PATENT OFFICE.

VVILLIAM A. MAOK, OF NORV'ALK, OHIO.

lMPROVEMENT IN SEWlNG-MACHINES.

Spccification forming part of Letters Patent No. l l l,39, dated January 31, 1871.

To all whom, it may concern.-

Be it known that I, WILLIAM A. Maori, of Norwalk, in the county of Huron and State of Ohio, have-invented certain Improvements in Sewing-Machines, of which the following is a specifieation.

My invention relates, first, to the feeding mechanism of a sewing-machine, coming technically under the head of drop,7 or fourmotioned feed, the required motion coming from an elevated main shaft; also, to the take-up77 device of a sewing-machine, eontrolled alternately by spring and positive motion; also, to shuttle, spring, and tension, and shuttle-head contrived to secure the greatest possible length of bobbin and evenness of tenson.

In the accompanying drawings, Figure l is a bottom View of the sewing-machine. Fig. 2 is a side view of the parts shown in Fig. 1. Fig. 3 is an end view of the same, and of the take-up and accessories. Fig. 4 is a cross- Section of facej 7 showing the needle-bar race. Fig. 5 is the shuttle and end piece. Fig. 6 is a View of the push-rod of the feed, from two positions.

a designates one arm of a double-armed device, and is of a piece with a collar or bearing held in place by the stay-nut sn, staying a pin in the slot s'.

a' designates the other arm, and grasps the extreme end of the push-rod pr, while a grasps that of the feed or walking-beam lever fl, neither too ti ghtly 5 a", an arm of the shuttle-lever sl; l), a ball on the end of the pendent lever pl,- b', the bearing of sl,- c, the cup of the rod cr, which has only vertical motion; (l, the take-up arm; e, the turned-up end of pr, to be inserted in the arm a",- h', the shuttle-head; i, the pin on the needle-bar ne,- j, the jaw of sl; k, the eye of the arm d; p, the shouldered end of pr; s, the feed or retreating spring; s", the slot for k, working in slot s'; sh, the shuttle piece; tb, the feed-bar; ip, the tension-spring of shuttle; is, the thumb-screw which regulates the step or stitch; and g is the shuttle.

The operation of the feed mechanism is as follows, viz: Oommencing at the moment when the shuttle arm or lever sl is about to carry the shuttle forward to engage the loop yet only incipient-ly formed by the thread of the descending or descended needle, the push-rod pr, its bent-up end e, socketed in the end of a short arm, a',, projecting from the side of the box, hub, or bearing b' of the shuttle-lever sl, lies across the shuttle-lever sl at a slight angle. The short arm a", being a part of the same casting and placed at right angles with the shuttle-lever sl 'at its bearing-point, is at this stage at the extreme point 'of its backward movement, as the sh uttle-lever also is. Consequently the moment forward movement` begins in the shuttle-lever sl endwise movement also begins in the push-rod pr, which is'curved or bent downward about one inch from its outer end at p, much like the handle of a shovel near the shovel-blade. The extreme point .beyond this curve passes through, first, the

toothed feed-bar fb, and then through the end of the arm a', directly under the toothed surface. Motion continuing, just before the shuttle reaches the other end of its are, the curved shoulder at p penetrates and positively crowds up the feed-bar tb against the cloth and presserfoot, preparatory to the feed motion of the same, with the cloth in charge. From about the tine when the shuttle reached the center of its are slight motion has been going on in the pendent connecting-rod cr, carrying its cup c into contact with the feed-adjusting screw t, which penetrates the end of the feed-lever jl. This lever jl has a sort of walking-beam action, given by the rod cr and the spring s, alternately. The absolute movement is given by the rod cr, and the opposite end thereof-i. e., of fl being inserted in the end of the arm a, this arm is depressed, and its right-angle arm a' is carried forward, taking with it the point p of the push-rod pr and the feed-bar tb, which is, as it were, strung thereon, and so arranged as to have endwise motion, as required. The forward feed-step having been made coincidentlywith the return of the shuttle, the push-rod pr withdraws its point p, and now the opposite side or curve of this point p operates to bring down the feed-bar tb, Which being done, the rod cr and cup o release the lever fi, and the spring s, taking it and the arms a and a' in charge, the feed-bar and push-rod are carried back to their starting-points, preparatory to a repetition of the movements described.

The backward and forward novements of the rod pr depend upon and co-operatewith those of the shuttle-lever where this feed is attached to a machine operating its shuttle in this manner. Manifestly, however, this kind of feed may be attached to machines driving their shuttles by other methods, in which case the part of the shuttle-level` in front of the bearing b'may be omitted without other modification. The part p of the rod pr is so shaped that the elevation and the depression of the feed-bar tb are positive.

The adjustment required by the wear of the toothed feed-surface is provided for by the suspension of the arms a and a', by a boss or bearing on a pin working perpendicularly in the slot s', wherein it is secured by the staynut s a. The pendent leverpl, which operates theshuttle-lever sland push-rodpr, is actuated by a cam on the main shaft and suspended on a pin below the same, has in this pendent part a pendulum-like motion; It is provided on its lower extremity with a ball, b, which takes in the jaws or fork j-of the shuttle-lever sl. The requirement of the position is harmony of two parts moving in two distinct planes at right angles with each other and both describing arcs, one giving and the other receiving power, as desired, with only a modicum of friction. The ball b touches the smooth sides ofthe fork or jaw j only at one point at a time, operating like auniversaljoint,and permitting all the play required by the exigencies of the position. As the motion alternates, the pressure and friction is transferred to opposite sides of the fork or jaw and ball.

The ball b may beso constructed or attached as to be turned when wear occurs thereon, and so present new surfaces for action.

The operation ofanother part ofmy invention is as follows, viz: The pin fi, fixed in the needlebar at the proper point, takes on the eoncave side of the take-up arm d, and actuates the same at each end of its motion. Starting, now, with the needle-bar elevated to its highest point and carrying the needle-thread in an eye at its top, the take-up arm d is' freed from the control of the pin z' soon after the downward movement ofthe needle-bar com meneesor rather the spring sp tends to keep the arm d in contact with the pin i throughout its motion; but owing to the concaved form thereof the arm d and the e ve k, at its end through which the thread passes, are moved over by the spring sp, the last in the slot s, thus taking in charge the slack in the thread developed by the descent of the needle-bar and drawing it in through the staple which straddles the slots'. Meantime the eye of the needle is slipping down on the thread to penetratethe cloth. After the needle penetrates the cloth the pin i strikes the lower limb of the eoncave arm d and drives its thread-ca rrying eye up to the staple again, by a positive action at the proper time, to give slack enough to permit the shuttle to pass through the loop. The eye k is as near as may be so held until the shuttle haspassed and the upward movement of the needle-barcommences, when, the pin i, tending to release the arm d, the slack left by the shuttle is gently taken up by the force of the spring sp, operating to carry the eye 75 to the opposite end of the slot again. The motion of the needle-bar continuing, the tightening of the stitch proceeds. As it (the pin i) strikes the upper limb of the take-up arm d and overcomes the spring sp, it compels the eye k to yield up the slack thread without its meeting with any resistance from that spring in ordinary cases, and yet if by any means more slack shall be required than is furnished thereby the spring sp will at once yield and prevent the thread from being broken, and supply the amount necessary. According, then, to the strength of the tension-spring, will be the pull of the needle-bar on the stitch, and in so far as that tension is overcome will there be a new supply of thread added to that already unspooled. From this point the movements described are repeated at each stitch.

The construction and operation of another improvementis as follows, via: Fig. 5, consisting of two parts, the largest showing the shuttle with the spring and tension piece ip in place, and the smaller showing an end View or a view of the head-piece h with the hook of the spring tp engaging the same, indicates the construction of my invention.

In my invention patented November 15, 1864, the flat spring was slightly bent at each endat the front end, so as to barely slip into the opening in the shuttle and engage the further side of the same, and at the rear end so as to slip into a groove in the shuttle-head, which screwed into the shuttle and thus covered this end. The defects of this shuttle, as above described, are, first, that the ends of the flat spring being only caught or covered, and not securely fastened, ito` would give and so furnish uneven tension; second, the screwhead took up valuable space, and would sometimes partially unserew and catch the needlethread between it and the shuttle, when it was surely broken. I'

In my present invention the flat spring is hooked at each end, and when in place cannot lift np or change the pressure on the thread,,

The hook bent over and hooked into the head not only firmly holds it in place, but furnishes a sort of guide, which conducts the thread safely off from the shuttle. The head h is a somewhat triangular piece, having a pin at the small end, intended to fit into a corresponding lout in the direction of the spring tp. Above the shoulder projects a piece or stem, rounded a trifie on the outer side and shaped to fit a notch made in the shuttle. This notch is eX- tended to one side, in order to let the hook engaged at its other end slip one side while the bobbin or head is being put in place. When the head reaches its place the hook of the spring tp is slid over it, or rather into the recess in its upper end, overwhich it curves and secures the head in place during use, acting also as a slide or guide to lead the needle-thread freeand off from the shuttle.

In use, the bobbin being inserted in the shuttle, the head h, which furnishes one bearing for the bobbin, is inserted, by first placing its pin in the hole made for it in the shuttle case or wall and pressing the other` end up into its place, thereby engaging the bobbinbearing of the outer end. When thus in place, the end opposite the pin projects through a recess prepared and fitting the same, and comes flush with the fiat wall of the shuttle, on which the tension-spring lies. This spring tp is a long and narrow piece of metal, more than two-thirds as long as the shuttle, and is provided with holes for the thread, the tension upon which is increased by the number of holes through Which it passes, and the consequent increase of pressure upon the multiplied parts pressed between the spring and the shuttle. It is also hook-shaped at each end. At that end toward the point of the shuttle it hooks into a square hole in the wall of the shuttle beyond the bobbin. At the other end provision is made to enable the hook to slip one side into a recess or nick in the wall of the shuttle while the end or head piece is being inserted. The thread from the bobbin is of course passed through the desired number of holes in the spring tp before the spring is slid over the head and set in place. The thread from the bobbin leading through the tension-holes, after passing the slit made for it, receives pressure in proportion to the size and strength, as Well as in proportion to the number of holes and spaces, thus giving full control over the tension of the shuttlethread. By these means a'very even tension is obtained, and space for a long bobbin.

The feed devices herein described are asso-l ciated more particularly with machines operating their shuttles by a horizontal lever describing part of a circle. Manifestly it relates to the class of machines actuated by a raised driving shaft, from Which the power and means of manipulation are derived, and may be applied to any of them, omitting the shuttle-carrying part where that is unsuited.

I claiml. The combination of the double-armed device a a, with the double-shouldered rod pr and the feed-bar tb. f

2. The shuttle-lever sl and pushing lever or rod pr, arranged and operating as described.

3. The combination of the pendent rod cr and the walking-beam lever jl,, for the purpose of operating the feed-bar ib.

4:. The combination of the adjusting thumbscrew is, pendent lever cr, and walking-beam lever fl, for the purpose of controlling the length of the step or stitch.

5. The combination of the walking-beam lever fl and double-armed feeding and retreating device a aj, for the purpose of giving motion to the feed-bar ib.

6. The shuttle-lever sl and pushing-rod pr, combined and operated by the pendent lever pl, as described.

7. The arm d, constructed as shown, and its springsp, operated by a pin on the needlebar, in vthe manner and for the purpose described.

8. The shuttle provided with the removable head h and hooked spring 1p, all constructed as described.

, VVILLIAM A. MACK.

Vitiiesses:

J AMI-:s BLAKE, J AMEs B. SKrL'roN. 

